Spark plug



F. M. EULER SPARK PLUG Original Filed June 6l 91g April 14, 1925.

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WIT/VESSEL? Patented Apr. 14, 1925.

UNITED STATES PATENT OFFICE.

FRANK MICHAEL EULER, OF IRVINGTON, NEW JERSEY.

SPARK PLUG.

Application led June 6, 1919, Serial No. 302.695. Renewed August 13, 1923.

To all 'whom t may concern.'

Be it known that I, FRANK M. EULER, a citizen of the United States, and a resident of Irvington, in the county of Essex and State of New Jersey, have invented a new and Improved Spark Plug, of which the following is a full, clear, and exact description.

This invention has for its object to provide a spark plug which is self-cleaning, which maintains a predetermined spark gap and which will economize the consumption of gasoline.

Other objects of the invention are to provide means to insure a normal and fat spark, even when the electro-des are a considerable distance apart; to provide means to cool the spark plug and the cylinder; to provide means to regulate the force of the explosion in the several cylinders, and thereby to insure the best results under dill'erent conditions and uniformity even should the piston rings in one of 'the cylinders be worn to a greater extent than the piston rings in the other cylinders; and to provide means to open communication between the cylinders and the atmosphere during the suction stroke and thereby increase the elliciency of the engine, as less power will, therefore, be required to move the piston during the said suction stroke.

Additional objects of the invention will appear in the following specification in which the preferred form of my invention is described.

In the drawings similar reference characters refer to similar parts in all the views, in which- Figure 1 is a sectional elevation showing the invention;

Figure 2 is an inverted plan view of Figure 1 lligiire 3 is a sectional fragmentary view showing the main valve; and

Figure 4 is a sectional view on the line 4 4 of Figure 3.

By referring to the drawings, it will be seen that the spark plug is constructed with porcelain 5 which may he much thinner than is ordinarily employed, inasmuch as it is cooled at each suction stroke of the engine. The danger of the porcelain cracking is eliminated by this periodic cooling. IThe porcelain5has an opening 6 extending there- Wthrough in which is disposed a metal tube 7 the metal tube 7 having an enlarged portion 8 below a valve seat 9. The lower portion 10 of the enlarged portion 8 of the metal tube 7 is threaded, and meshing in this thread 10, there is a threaded portion 11 of a companion tube 12. This companion tube 12 has an inner thread 13, in which is disposed a screw 14 having a head 15 which serves to press the spring 16 against a ball or other valve 17, normally seated at the valve seat 9. The lower end 18 of the tube 12 serves as an electrode, the other electrode 19 being integral with a spring portion 20 which is disposed in a groove 21 at the lower portion of the spark plug shell 22. The porcelain 5 is preferably provided with a shoulder 23 which is gripped between the spark plug shell 22 and the nut 23a. rlhe spark plug shell 22 has an outer thread 24 by which means the spa-rk plug is screwed in a cylinder head. A wire or terminal is connected with the metal tube 7 beyond the porcelain 5 by means of the screw or nut 25 which screws on the outer thread 26 at the outer end of the tube 7.

It will be understood that it is possible to regulate the tension of the spring 16 by means ofthe screw 14, so that theicylinders of the engine will operate uniformly whether or not the piston rings in one or more of the cylinders are worn to a ygreater extent than in the other cylinders and whether other abnormal conditions may present themselves in one or more of the cylinders.

At the suction stroke of the engine not only will the inlet valve be open, but the valve 17 will be drawn away from its seat 9 to permit air to enter the cylinder through the tube 7 which will not only serve to cool the tube 7 and porcelain 5 and cleanse the electrodes 18 and 19 and the lower portion of the shell 22, but will also serve to introduce a considerable quantity of oxygen to mix with the combustible mixture entering the cylinder through the inlet valve. ln addition, there will be a considerable quantity of oxygen in the mixture at the electrodes 18 and 19 when the combustible mix-y ture is fired by a spark jump-ing from one electrode to another. The air will enter the cylinder through the tube 7 and the valve seat 9 and out of the enlarged portion 8 of the tube 7 through the openings 27.

l'n addition to the valve 17, I ,illustrate a im p second valve 28 which is normally raised from the valve seat 29 at the outer end of the tube 7 but which may be under the control of the chauffuer or operator so that he may close the valve 9 when desired.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

l. In a spark plug, a tubular shell, a central tube in said shell, insulating means spacing said central tube from the shell and terminating short of both the inner end of the shell and the inner end of the central tube, an annular space thus being produced between the inner end portions of the tubular shell and the central tube, said central tube being enlarged adjacent to its inner end, said enlargement terminating short of the inner end of the central tube and hav. ing a lateral opening, the outer end of the enlarged port-ion of the central tube defining a valve seat within the central tube, a valve movable within said enlargement, a spring within said enlargement urging said valve against said valve seat, and a screw threaded in the inner end portion of said central tube for adjusting the pressure on said spring and for closing said central tube inwardly of the lateral opening of said enlargement.

2. ln a spark plug, a tubular shell, a central tube in said shell, insulating means spacing said central tube from the shell and terminating short of both the inner end of the shell and the inner end of the central tube, an annular space thus being produced between the inner end portions of the tubular shell and the central tube, said central tube being enlarged adjacent to its inner end, said enlargement terminating short of the inner end of the central tube and having a lateral opening, the outer end of the enlarged portion of the central tube dening a valve seat Within the central tube, a valve movable within said enlargement, a spring within said enlargement urging said valve against said valve seat, a screw threaded in the inner end portion of said central tube for adjusting the pressure on said spring and for closing said central tube inwardly of the lateral opening of said enlargement, and an outwardly opening manually operable valve adapted to seat against the outer end of said central tube.

FRANK MICHAEL EULER. 

